/Engine/Plugins/Animation/IKRig/Source/IKRig/Public/Retargeter/IKRetargeter.h
Set the chain Speed Plant settings in a retarget profile (will set bApplyChainSettings to true).
[UFUNCTION](Programming/UnrealArchitecture/Reference/Functions)(BlueprintCallable, Category=RetargetProfile) static void SetChainSpeedPlantSettingsInRetargetProfile ( [FRetargetProfile](API\Plugins\IKRig\Retargeter\FRetargetProfile) & RetargetProfile, const [FTargetChainSpeedPlantSettings](API\Plugins\IKRig\Retargeter\FTargetChainSpeedPlantSettings) & SpeedPlantSettings, const [FName](API\Runtime\Core\UObject\FName) TargetChainName )